Hárið mitt er blautt eftir sturtu.

A very literal breakdown is:

• Hárið = the hair
• mitt = my
• er = is
• blautt = wet
• eftir sturtu = after a shower / after showering

So the structure is basically The hair my is wet after shower.
That sounds odd in English, but it is normal Icelandic.

Because -ið is the definite article attached to the end of the noun.

• hár = hair
• hárið = the hair

Icelandic usually puts the onto the noun itself instead of using a separate word like English does.

With possessives, Icelandic very often uses the pattern:

definite noun + possessive

So:

• hárið mitt = my hair
• literally: the hair my

This is one of the most normal everyday ways to say it.

Mitt hár is also possible, but hárið mitt is especially natural in ordinary speech here.

Yes, if you translate it word for word, it looks like that. But in Icelandic this is completely normal.

English and Icelandic handle possession differently:

• English: my hair
• Icelandic: hárið mitt = literally the hair my

So even though it feels strange from an English point of view, it is standard Icelandic grammar.

Because mitt has to agree with hár, and hár is a neuter singular noun.

The possessive forms are:

• minn = masculine
• mín = feminine
• mitt = neuter

Since hár is neuter, Icelandic uses mitt.

Because the adjective has to agree with hárið, which is neuter singular.

The adjective blautur (wet) changes form by gender:

• blautur = masculine
• blaut = feminine
• blautt = neuter

So:

• hárið is neuter
• therefore blautt must also be neuter

This agreement still happens even though the adjective comes after er.

Yes, it is singular.

In Icelandic, just like in English, hair can be treated as a general mass/collective noun:

• hárið mitt = my hair in general

If you wanted to talk about individual hairs or strands, then a plural expression could be used instead.

So here the singular is exactly what you would expect.

Because after the preposition eftir (after), the noun does not stay in its basic dictionary form.

The basic form is:

• sturta = shower

But after eftir, it becomes:

• sturtu

This is part of Icelandic case grammar: prepositions often force the following noun to change form.

Because Icelandic often leaves the noun without an article in phrases like this.

So:

• eftir sturtu = after a shower / after showering

It sounds general and natural.

If you meant a specific shower already known in the conversation, you could say:

• eftir sturtuna = after the shower

Yes. In natural English, this sentence could be understood as either:

• My hair is wet after a shower
• My hair is wet after showering

The Icelandic phrase eftir sturtu is a normal compact way to express that idea.

Yes. Icelandic word order is fairly flexible.

The given sentence is a neutral, natural order:

• Hárið mitt er blautt eftir sturtu.

But you could also say:

• Eftir sturtu er hárið mitt blautt.

That version puts more focus on after a shower at the beginning. Both are natural.